Daily low-dose aspirin associated with falls in healthy older people

Healthy older patients who take low-dose aspirin daily may be at higher risk for falls, a recent study found.

Researchers performed a substudy of the ASPREE trial, a double-blind, randomized, placebo-controlled trial that recruited healthy community-dwelling adults in the U.S. and Australia between 2010 and 2014 and assigned them to receive 100 mg of enteric-coated aspirin daily or an identical placebo. The substudy, the ASPREE-FRACTURE trial, involved only patients from Australia because falls and fractures, which were reported at annual visits or at six-month follow-up by telephone, could not be properly verified by documentation in U.S. patients. ASPREE-FRACTURE's primary outcome was any fracture; the secondary outcome was serious falls, defined as those that led to presentation at a hospital. Bayer AG provided the study drug. The results were published Nov. 7 by JAMA Internal Medicine.

Overall, 16,703 patients were included in the trial, 8,322 in the intervention group and 8,381 in the control group. The mean age was 74 years, and 55.0% were women. A total of 1.2% of patients withdrew from the study and 1.6% were lost to follow-up. Over a median follow-up of 4.6 years, there were 2,865 fractures and 1,688 serious falls. The intervention and control groups did not differ in risk for first fracture (hazard ratio, 0.97 [95% CI, 0.87 to 1.06]; P=0.50), but aspirin was associated with higher risk for serious falls, with 884 in the intervention group and 804 in the control group (incidence rate ratio, 1.17 [95% CI, 1.03 to 1.33]; P=0.01). These results persisted in analyses that were adjusted for covariates known to affect risk for fractures and falls, including age, medications, and alcohol use.

The researchers noted that the study was done in mostly healthy people and that meaningful changes in fracture and fall risk might not have had time to develop over the duration of the intervention, among other limitations. “In this substudy of a randomized clinical trial, the lack of an effect of low-dose aspirin on the risk of fractures while increasing the risk of serious falls adds to the body of evidence that this agent provides little favorable benefit in a healthy, White older adult population,” the authors wrote. Their results may have clinical significance due to the many older patients who are at risk for fracture and are taking aspirin for prevention of cardiovascular and cerebrovascular disease, they said.

Another study, published Nov. 8 by BMJ, involved the development and external validation of a fall risk prediction model in patients who had an indication for antihypertensive treatment. Researchers used primary care data from electronic health records in the United Kingdom for patients ages 40 years and older who had at least one blood pressure measurement between 130 mm Hg and 179 mm Hg. The main outcome measure was the first serious fall, defined as hospital admission or death with a primary diagnosis of a fall within 10 years of the index date.

The model was made up of 24 predictors, including age, sex, ethnicity, alcohol consumption, history of falls, and prescriptions of antihypertensives, antidepressants, hypnotics, and anxiolytics, and was able to distinguish between patients who were at low and high risk for falls for up to 10 years. Although external validation showed miscalibration, the model could have potential clinical utility at risk thresholds of 10% and could be used to identify patients in clinical practice who may need closer monitoring or early intervention, the authors said. They called for further studies to determine the best thresholds for maximizing the model's clinical utility and cost-effectiveness.